Hi. Well, this is a weird question but I have to ask since you mention your period. Any chance you forgot a tampon in there? Had sex with it and it got pushed up? This is easy to do and will cause severe odor and discomfort. If not, then I'd guess bacterial infection and I would go ahead and make that doctor's appointment. Antibiotics are needed to eliminate bacterial vaginosis. And that is a tricky infection and doesn't go away some times the first try. Basically the pathogens involved love an anaerobic environment (no air, hot moist). So, try to air yourself out by sleeping with out undies, wear cotton undies, change when you work out or sweat a lot, etc. But really, I think you need to see a doctor as a foul smell is a hallmark sign of vaginal infection. good luck
U might be pregnant.take a pregnancy test.if your not pregnant then your womb is cleaning.but u must also visit a doctor